Video: Slack vs Yammer


Slack brings all your communication together in one place. It's real-time messaging, archiving and search for modern teams. Create open channels for the projects, groups and topics that the whole team shares. Slack searches whole conversations, not just individual messages, so you can find what you’re looking for no matter who said what or when they said it. Slack free open-source (self-hosted) alternatives are: Mattermost, Rocket.Chat, Zulip
Yammer is revolutionizing internal corporate communications by bringing together all of a company’s employees inside a private and secure enterprise social network. Although Yammer is as easy to use as alternative consumer products like Facebook or Twitter, it is enterprise-class software built from the ground up to drive business objectives.
Face to face in the news:


2017 - Slack raised $250 million at $5 billion valuation to take on Yammer


Enterprise messaging service Slack is raising a $250 million round at a $5 billion valuation. Slack has almost a cult following in Silicon Valley, but much of its success will be contingent on whether it is able to convince large enterprises around the world to switch services. Slack has touted itself as an alternative to email, but it’s not a platform for communicating with people outside your company. A lot of people love Slack over Yammer for its modern interface.

2017 - Microsoft retired Yammer as stand-alone service to keep up with Slack


Microsoft is replacing the stand-alone enterprise social network Yammer in favor of deeper levels of integration with Office 365 services. Last year Microsoft turned on Yammer by default for all eligible Office 365 customers. Since then, the vast majority of Yammer customers use it as part of an Office 365 subscription. The new customers that want to use Yammer will have to sign up for an eligible Office 365 plan. In a notice about Yammer, Microsoft explained it was "strengthening Yammer integration" with various Office 365 collaboration tools including SharePoint, OneNote and Planner.